Speed-indicator for calling devices.



J. ERIGKSON.

SPEED INDICATOR FOR GALLENG DEVICES,

APPLICATION FILED OCT. 30, 1911v m m A, m m Mm 1 m A d m 3 A N? 1 Waaare controlled over a metallic line circuit,

- to determine when the calling device was UNITED STATES PAT JOHNERICKSON, OF CHICAGO, ILLINOIS, ASSIGNOR T0 AUTOMATIC ELECTRIC COM-PANY, OF CHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS.

SPEED-INDICATOR FOR CALLING DEVICES.

Specification of Letters Patent.

Application filed October 30, 1911.

Patented Oct. 6, 1914.

Serial No. 657,594.

To all whom it may concern Be it known that I, JOHN E-RICKsoN, a;citizen of the United States of America, and resident of Chicago, Cookcounty, Illinois, 5 have invented certain new and useful Im-j provementsinSpeed-Indicators for Calling l Devices, of which the following is aspecilioalion.

My invention relates to a speed indicator for culling levi(.-es-that is,to a mechanism for indicating when a. calling device for an automatictelephone system is operated at the propcrspecdQ It is very essential tothe successful operation of automatic switches in an automatic telephonesystem, especially those known as the two-wire typethat is, switcheswhich that the calling device should operate at the proper speed so asnot to transmit the impulses which operate the switch either too fast ortoo slow. In order to control the speed, the calling device is providedwith an adjustable governor, .which governor must be adjusted so thatthecalling devices will run at the proper speed. I-Ieretofore, the oneadjusting the calling device has had to depend merely upon his ownjudgment properly adjusted. The usual manner was to connect the callingdevice with an automatic switch. and by observing the. operation of thisswitch when the calling device was operated to decide whether or not theadjustment was correct.

My present invention relates to a device by means of which the adjustercan deter mine absolutely when the calling device is adjusted to operateat the proper speed, and comprises an indicating mechanism which willindicate when the calling device is operating at a correct speed, andwill also indicate how much too slow or too fast the calling device isoperating.

While I have illustrated my invention as being particularly adapted foruse in connection with calling devices of an auto matic telephonesystem, it will be readily understood that my invention is not limitedto such use, but may be used in many other instances where it is desiredto obtain an indication of when a device is operating at the properspeed.

In theaewmpanying drawings Figure 1 l is a front view of the device.Fig. is a side view of the same. Fig. 3 is a View of a section on theline 3-3 in Fig. 2. Fig. 4.- is aview of a suction taken on line 4-4 inFig. 2.

The frame for the mechanism comprises two plates 2 and 3 which aresecured to and separated from each other by the posts 4: and 5 and theblock 6. Journaled in the plates 2 and 3 there is a shaft 7 to whichthere is firmly secured, outside of the plate 2, a. key 8 and a. lever9. Loosely mounted on the shaft 7, between the plates 2 and 3.

. there are two gear wheels 10 and 11 which are provided with theactuating springs 12 and 13', respectively. The gear wheel 10 mesheswith a pinion lat (Fig. 4) which is firmly secured to a shaft 15, whichshaft is journaled in the side plates. -Likewise so cured to the shaft15 there is a ratchet wheel 16. Loosely mounted upon the shaft 15. andcarrying a. pawl 17 which cooperates with the ratchet wheel 16, there isan 95-, capement wheel 18, cooperating with which there is a smallcscapemen'tlever 19.

The gear wheel 1-1 meshes with a pinion LZO-(Fig. 3) which is firmlywired to a shaft 21, to which latter there is also seured an escapcinentWheel-22. Cooperating with the escapement wheel 22 there is anescapement lever 23. Mounted upon the lower side of the h'lock 'there isan electro magnet 24, having a pivoted" armature "213. A link 26connects the armature 2-5 with the csc'ipcment lever 23.

From the abov description it will he seen that the mechanism comprisestwo separate $56211 trains, one of. which is shown in Fig. -3 and theother in Fig. 4. each having ascparate driving spring and csca-pementdevice. To the gear wheels 10 and 11 therev are attached the pointers orindicators 31; and 27, respectively. Rolatahly mounted upon a. pin 29there is a lever 30, the upper end of which projects up between thewheess 10 and 11 and into the path of the pins 31 and 32 on the wheelll.Vhen either of the pins 31 or 32 passes the upper end of the lever 30,its lower end is forced into engagement with the small three-sided pin 3which projects laterally from the side of the emtpement lever 19.Insulatingly mounted upon the face of the plate 2 there is a pair ofcontact springs 34 and 35 which are adapted to be forced into contact bya bushing 9on the lever 9 when it is in the posi tion shown.

If the key 8 be turned in a counterclockwise direction the rearwardlyextending portion of the lever 9 (Fig. 2) may be caused to forcetheindicators 27 and 28 upon frees the escapement lever 19.

over until they strike the post 4-, thereby rotatinh the wheels 10 and11 and winding, up the springs 12 and 13. When the indicators are thusforced over against thepost 4, the pin 32 in the wheel 11 comes intoengagement with the upper end of the lever 30, forcing it back so as tocause the lower end of said lever to engage the pin 33 to lock theescapement lever 19 to prevent the wheel 10 and pointer 28 fromreturning to their original positions. The wheel 11 is locked in itsadvanced position by the engagement of its escapement wheel 22 with theescapenient lever 23. The lever 23 cannot be vibrated by its escapementwheel as can the lever 19, and the only way the wheel 11 can be returnedto its original position is by energizing and de'nergizing the magnet 24a number of times to permit the wheel 22 to escape step by step.- Assoon as the wheel 11 rotates one step. on its return-movement, the pindisengagesthe lever 30, which there- The wheel 10 thereupon begins torotate back to its original position, its speed being governed by theescapement lever 19. The pin 31 in the wheel 11 is placed in such aposition that after the wheel 11 has completed a predetermined number ofsteps on its returnrotation, said pin engages the end of the lever 30,causing it to again lock the escapement lever 19 and arrest the motionof the spring 12 and pointer 28.

The manner of using the device is as follows: The magnet 24 is connectedin circuit with the calling device to be tested and a source of current,and the key 8 is turned to bring the pointers'27 and 28 over against thepost 4. The calling device is now operated in the usual manner, usuallyfor the highest number of impuses which it will call. These impulsesmomentarily open and close the circuit of the magnet 24, which results,as has been explained, in causing the pointer 27 to be rotated back toits original position step by step in synchronism with the impulses. Assoon as the pointer 27 is rotated the first step, the pointer 28 isunlocked and begins its independent return movement. The mechanism is soadjust-ed that the pointer 28 completes its return rotation in the timewhich isrequired for the calling device to complete its series ofimpulses when it is operating at the proper speed. Therefore, if thecalling device is operating at the proper speed, the pointers 27 and 28will sweep over their arcs at the same speed. If the calling device isrunning too fast, the

pointer 27 will run ahead of the pointer 28, and if the calling deviceis operating too slow, the pointer 27 will lag behind the pointer 28. Asexplained, the lever 9 is arranged to close the springs-34 and 35 whenit is forced by the pointers to the position shown. Thesprings 34 and 35are arranged to short-circuit tin; calling device. Therefore, as soon asthe pointer completes its travel, the calling device is short-oircuitedand no more impulses can be delivered to the magnet 24, and the pointer27 will come to rest. If the calling device is slow. the arm 27 will nothave completed its travel when it comes to rest, and the position inwhich it stops will indicate how much too slow the calling device If thecalling device is too fast, all the impulses will be delivered to themagnet and the arm 27 will come/to rest before the pointer 28 completesits travel. The pin 31 in the wheel 11 is placed so that it strikes thearm 30 and locks the eseapemcnt 19 when the magnet- 2-1 is energizedafter the last impulse is delivered by the calling device. Therefore,the arm 28 will be brought to rest before it completes its travel andthe position in which it stops indicates how much too fast thecalling'device is.

While I have illustrated one specific form of my invention, it-will beunderstood that I do not wish to be limited to such an exact structure,as many specific mechanical changes may be made without departing: fromthe spirit and intent of my invention.

What I claim as my invention is? 1. In a. speed indicator for calling dovices, a pair of pointers, means for moving one of said pointers at apredetermined speed, means for moving the other of said pointers insynchronism with the calling device being tested, and means whereby thefirst pointer is started in operation by the operation of the secondpointer.

2. In a speed indicator for calling devices, a pair of pointers, meansfor movin one of said pointers at a predetermine speed, step-hy-stepmeans for moving the other of said pointers in synchronism with thecalling device being tested, and means whereby the second pointer locksthe first pointer against movement.

3. In a speed indicator for calling devices, a pair of pointers, meansfor rotating one of said pointers at a predetermined speed, means forrotating the other of said pointers a predetermined distance in s vnchronism with the calling device being tested, and means for stoppingeither of said pointers when the otherreaches the limit of its movement.

4. In a speed indicator for calling devices. a pair of pointers locatedadjacent to one another, means for moving one of said pointers at apredetermined speed, means for moving the other of said pointers and anescapcment mechanism operated in syn'chromsm with the calling devicebeing tested for controlling the speed of said other i pointer.

5. In a speed indicator for calling devices, a pair of pointers, meansfor moving one of said pointers at a predetermined speed, and means formoving the other of said pointers step by step in synchronism with thecalling device being tested, means for limiting the extent of movementof said pointers, andmeans for stopping bot-h of said pointers when onereaches the limit of its movement. Y v i v '6. In a speed indicator forcalling devices, a pair of pointers, means for moving said pointers, anescapement mechanism controlling the movement of one of'said pointersand adapted to move the same at a predetermined speed, a secondescapement mechanism for controlling the movement of the other-of saidpointers, and a magnet for controlling the second escapement adapted tobe energized iu synchronism with the impulses transmitted fromthecalling device being tested' 7. 'In a speed indicator for callingdevices, a pair of movable ointers, a separate train of gears for controling the movement of each of said pointers, means for moving one'of saidpointers a predetermined distance, means for moving the other of saidpointers, and means for-stopping either of said pointers when the otherpointer has reached the end of its movement.

8. In a speed indicator for calling devices, a pair of movable pointers,means for moving said pointers, an escapement mechanism for controllingthe movementof each of said pointers. means for moving said pointersfrom one position to another, means for holding said pointers in saidsecond position, a magnet adapted to be operated in synchronism with theimpulses transmitted from the calling device being tested forcontrolling the movement of one of said pointers, and means forreleasing said second pointer and permitting it to return to said firstposition at a. predetermined speed upon the initial energization of saidmagnet.

9. In a speed indicator for calling devices, a pair of movable pointers,means for moving one of said pointers a predetermined distance, meansfor movin the other in synchronism with ,the calling device, and meansfor stopping the first-mentioned pointer when the second pointer reachesthe limit of' its movement.

Signed by me at Chicago, Cook county, Illinois, this 26th day ofOctober, 1911.

JOHN ERICKSON.

lVitnesses:

ARTHUR J. RAY, E. D. Fauzs.

